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arXiv · 2411.07295

Smooth extremal horizons are the exception, not the rule

Gary T. Horowitz·Jorge E. Santos
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Abstract

We show that the general charged, rotating black hole in five-dimensional Einstein-Maxwell theory has a singular extremal limit. Only the known analytic solutions with exactly zero charge or zero angular momenta have smooth extremal horizons. We also consider general black holes in five-dimensional Einstein-Maxwell-Chern-Simons theory, and show that they also have singular extremal limits except for one special value of the coefficient of the Chern-Simons term (the one fixed by supergravity). Combining this with earlier results showing that extremal black holes have singular horizons in four-dimensional general relativity with small higher derivative corrections, and in anti-de Sitter space with perturbed boundary conditions, one sees that smooth extremal horizons are indeed the exception and not the rule.

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Gary T. Horowitz, Jorge E. Santos. 2024-11-11. Smooth extremal horizons are the exception, not the rule. https://arxiv.org/abs/2411.07295

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